I think the colors. They are chosen to make such warm feeling. That is the same if you look landscape photos from usual camera and by a professional photographer.
This doesnt mean that some pictures are worse, but the style is different. Look at food photos for commercials, colors there are not "real" but somekind "tale" style. The 4th picture is more natural and realistic (but realistic doesnt mean attractive). Modern games are using often such "hot" colors.
2d achieves this result easier. You just need the right palette.